Bus-Clamping Based Improved Discrete Duty Ratio Control Technology of Direct Torque Control for Induction Motors

Abstract

One of the disadvantages of traditional direct torque control is high torque ripple, A method of reduce torque ripple was proposed basing bus-clamping and duty ratio control technique in this paper. Firstly, the switch vector table with bus-clamping technology was improved by analyzing the role of zero voltage vector to reduce torque ripple in different sector of voltage. Secondly, on the base of combing the improved bus-clamping direct torque control (BCDTC) and discrete duty ratio control (DDRC), a new switch vector table with discrete duty ratio and bus clamping was designed by analyzing the role of zero voltage vector to reduce torque ripple in different speed range. Finally, simulations are performed to verify the proposed strategies.